The 56-year-old actress congratulated and sent birthday wishes to Meloni on his 59th birthday Thursday on Instagram following news he will reprise his SVU character, Elliot Stabler, in a new NBC series.
"Happy Birthday @chris_meloni," Hargitay wrote. "Congratulations and welcome home Elliot Stabler #It'sBeenAWhile #MissedYou #ElliotStabler."
Meloni thanked well-wishers and showed off his homemade birthday cake in a photo Thursday.
"Got my fam. Homemade cake. Health. #luckyman #thxfortheBDayshouts," he captioned the post.
News broke Tuesday that Meloni will reprise Stabler in a new series created by Dick Wolf. The show will be part of the Law & Order franchise and will focus on the NYC police department organized crime unit that Stabler led on SVU.
Meloni appeared to confirm the series on Twitter.
Hargitay and Meloni have reunited several times since Meloni's exit from SVU in 2011, including for a Sunday night dinner in September.
Meloni is also known for playing Chris Keller on Oz, August Pullman on Underground and Nick Sax on Happy!. He voices Commissioner James Gordon in the DC Universe animated series Harley Quinn.